mmap summary

• The device driver is loaded. It defines an mmap file operation.

• A user space process calls the mmap system call.

• The mmap file operation is called. It initializes the mapping using the device physical address.

• The process gets a starting address to read from and write to (depending on permissions).

• The MMU automatically takes care of converting the process virtual addresses into physical ones.

Direct access to the hardware! No expensive read or write system calls!